Indianapolis - Fernando Alonso's latest bid for Indianapolis 500 glory ended in failure on Sunday after the two-time Formula One world champion failed to qualify for the US motorsport showpiece.

The 37-year-old Spaniard was eliminated by young US driver Kyle Kaiser on the final run of the rain-delayed "Last Row Shootout" qualifying session at Indianapolis Motor Speedway.

McLaren driver Alonso had been chasing a victory at the Brickyard in a bid to become only the second driver after Britain's Graham Hill to claim the Triple Crown of motorsport, with wins in the Monaco F1 Grand Prix, 24 Hours of Le Mans endurance and Indy 500.

But Alonso's attempt to add the last remaining piece of the Triple Crown to his trophy cabinet was snuffed out in a dramatic qualifying session.

McLaren engineers had worked feverishly on the Spaniard's car in an effort to give him a fighting chance of qualifying for next week's race, overhauling the setup after a troubled week in Indianapolis.

The tweaks looked to have given Alonso a shot as he took to the track and posted an average time of 227.353mph for his four laps, putting him second behind Canada's James Hinchcliffe.

However Alonso was left sweating after Sage Karam came out next and roared to the top of the six-driver session with an average speed of 227.740mph.

Karam's time dropped Alonso down to third fastest, and with only the top three making the cut to complete the 33-car field, the Spanish star was left with a nervous wait to see if either of the two remaining drivers could better his time.

Alonso watched anxiously on a television monitor in the pits as Mexico's Carlin driver Patricio O'Ward failed to pip him, clocking an average speed of 227.092mph.

That left Kaiser with the chance to claim a famous scalp on the final run.

The 23-year-old Juncos Racing driver from California didn't disappoint, sweeping around with an average speed of 227.372 to edge out Alonso by the tightest of margins.

"I don't think I can wrap my mind around what we just did," Kaiser said afterwards.

"All the credit to the team. They've been working non-stop to get this car ready. I'm so proud of them, so proud of everybody that helped make this happen."

Kaiser's qualification had looked in doubt earlier this week, when he crashed heavily in Friday's practice.

However he insisted he had never lost hope of being able to qualify.

"I did imagine it and I'm so happy it came to fruition," he said.

"But I knew it was going to be a lot of work and the team put in the work. It's been the most emotional 48 hours of my life.

"I've been doing everything to try and keep a level head, go about my business and just keep telling myself it's only four laps. And we did it."

In qualifying to determine the front of the grid later on Sunday, France's Simon Pagenaud swept to pole position in the "Fast Nine" session.

Pagenaud, the 2016 IndyCar champion, gave Penske its first Indy 500 pole in seven years after he roared around with an average speed of 229.992mph.